A substance that slows or interferes with the reaction of a fat or oil with oxygen. The addition of antioxidants to fats or foods containing them retard rancidity and increases stability and shelf life.


The purification process to remove color bodies and residual impurities from oils and fats during refining, generally through the use of an adsorbent clay material.


The use of living organisms or other biological systems to develop food, drugs and other products.


A material which accelerates a chemical reaction without becoming part of the reaction products.


A fat-soluble sterol found primarily in animal cells important in physiological processes.


A natural, green coloring agent vital to a plant’s photosynthesis process which is removed from vegetable oils through bleaching and refining processes.


The term applied to a geometric isomer of an unsaturated fatty acid where the hydrogen atoms attached to the carbon atoms comprising the double bond are on the same side of the carbon chain.

Cold Press

Extraction process whereby oil bearing materials are mechanically pressed without any heat treatment.

Confectionery fat

A broad range of fats with steep melting profiles used in the formulation of sweet goods such as candy bars, bakery product coatings, cream centers, and granola bars.

Conjugated fatty acids

Polyunsaturated fatty acids exhibiting two or more of unsaturated carbons atoms not separated by a saturated carbon atom.

Crude oil

The oil product obtained from the initial extraction, either mechanical and/or solvent based, of an animal or vegetable source.


The process that removes phosphatide compounds from crude oils prior to refining.


The process of subjecting oil to high temperatures in the presence of a vacuum to remove trace volatile components that may affect flavor, odor and color. It is generally the last step in the refining process.


Removal of natural waxes from edible oils


The glycerol ester containing two fatty acids.


Compounds having the ability to reduce surface tension at the interface. Emulsifiers are often used to disperse immiscible liquids such as water and oil or fats in products such as mayonnaise, ice cream and salad dressings.


The condensation reaction product of an alcohol and an acid.


The reaction of chemically combining an alcohol and an acid resulting in the formation of an ester.

Expeller pressed

Mechanically separated oil from oilseed meal.


Esters of fatty acids and glycerol which are normally solid at room temperature.

Fatty Acid

A long chain carboxylic acid, which generally contains an unbranched chain with even number of carbons.

Fully refined oil

The term used to describe an oil which has been subjected to extensive processing methods to remove: (1) free fatty acids and other impurities (refining), (2) naturally occurring color bodies such as chlorophyll (bleaching), and (3) volatile trace components which may affect color, flavor and odor (deodorizing).

Fire point

The temperature at which an oil sample, when heated under prescribed conditions, will ignite for a period of at least five seconds (spontaneous combustion).

Flash point

The temperature at which an oil sample, when heated under prescribed conditions, will flash when a flame is passed over the surface of the oil but not maintain ignition.


The process of separating fats and oils by differences in melt points, solubility or volatility.

Free fatty acids

The fatty acids in a fat which are not chemically bound to glycerol molecules.

Fully hydrogenated

The term describing a fat which has been hydrogenated to the completion or near completion of saturation, which results in significant chemical and physical changes.  Changes include, transformation of liquids to solids at room temperature, and increase in melt point, solid content, saturation, and stability. As conversion to saturation is complete, trans isomers are not formed. Products containing hydrogenated fats include “heavy duty” frying fats for restaurant use, solid shortenings, confectionary coatings, peanut butter stabilizer, and solid margarines.

Geometric isomer

A type of isomer distinguished because of its structural location of certain elements.


A three-carbon chain alcohol molecule with chemical formula, C3H803. Also known as glycerin. When combined with one, two, or three fatty acids forms a mono, di, or triglyceride, respectively.


A required term identified in the Food & Drug Administration’s labeling regulations (21 CFR 101.4(b) 14) relating to hydrogenated fats and oils. The term indicates a fat or oil is completely hydrogenated. See “fully hydrogenated.”


The reaction of adding hydrogen atoms to the carbon-to-carbon double bonds in unsaturated fatty acids. This process results in increased melt points, higher solid fat content, and longer shelf life without rancidity in fat-containing products.


The splitting reaction of fat with water to form glycerol and free fatty acids.


The reaction of rearranging the fatty acids in triglyceride molecules. It is used principally in confectionery fats, table spreads, shortenings, and margarines to maintain solid fat content at ambient temperatures while lowering the melting point.

Iodine value

An expression of the degree of unsaturation of a fat. It is determined by measuring the amount of iodine which reacts with a natural or processed fat under prescribed conditions.


Compounds containing the same elements in the same proportions which can exist in more than one structural form; e.g. geometric, positional or cyclic.

Lauric oils

Oils containing 40-50% lauric acid (C-12) in combination with other relatively low molecular weight fatty acids. Coconut and palm kernel oils are principal examples.


A mixture of naturally occurring phosphatides which has emulsifying, wetting and antioxidant properties, a principal source of which is crude soybean oil.


A broad spectrum of fat and fat-like compounds including mono-, di- and triglycerides, sterols, phosphatides and fatty acids.


Any of the class of proteins that contain a lipid combined with a simple protein.

Medium chain triglyceride (MCT)

Triglycerides containing fatty acid chains of 6-10 carbon atoms.

Mixed triglyceride

A triglyceride containing two or three kinds of fatty acids.


The glycerol ester containing only one esterified fatty acid.

Monounsaturated fatty acid

A fatty acid containing only one carbon – carbon double bond.

Non-conjugated fatty acids

Polyunsaturated fatty acids exhibiting two or more double bonds separated by at least one saturated carbon atom.


Esters of fatty acids and glycerol which normally are liquid at room temperature.


An ester or salt of oleic acid.


The liquid fraction when an oil or fat is fractionated.


A sucrose fatty acid polyester used as a substitute for dietary fat which is not digested or absorbed by the body.


The reaction of oxygen with a fat or oil resulting in the development of rancidity.

Partially hydrogenated

 A required term identified in the Food & Drug Administration’s labeling regulations (21 CFR 101.4(b) 14) relating to hydrogenated fats and oils. Partially hydrogenated oils are limited in degree of hydrogenation, as compared to completely hydrogenated oils. Light to moderate hydrogenation results in limited increases in melting properties, while improving stability.


The primary compounds formed from the oxidation of unsaturated fatty acids, which may react further to form the compounds that can cause rancidity.


The chemical combination of an alcohol (typically glycerol) with phosphoric acid and a nitrogen compound; synonymous with phospholipid.


The process of creating a solid crystal structure in a fat or oil product resulting in a smooth appearance and firm consistency.


The bonding of similar molecules into long chains or branched structures.


The property of a fat molecule to exist in multiple crystalline structures; mainly identified as alpha, beta and beta prime.

Polyunsaturated fatty acid

A fatty acid containing more than one carbon-carbon double bonds.

Positional isomer

An isomer distinguished by the location of a double bond.


The process of removing impurities from crude oil by way of treatment with alkali solution (chemical) or steam stripping (physical).


The chemical reaction between a fat or oil and an alkaline compound creating glycerol and soap.

Saturated fatty acid

A fatty acid containing no carbon-carbon double bonds.


A fat product that incorporates tenderness in the food (e.g., bakery products) in which it is used. It may carry other additives such as flavorings, colors, emulsifiers and preservatives.

Simple triglyceride

A triglyceride comprised of three identical fatty acids.


The salt of fatty acids.

Soap stock

The aqueous byproduct from the chemical refining process that is comprised of soap, hydrated gums, water, oil and other impurities.

Smoke Point

The temperature at which an oil sample, when heated under prescribed conditions, will form a thin continuous stream of smoke.


The solid product when an oil or fat is fractionated.

Stearic acid

A saturated 18-carbon free fatty acid.


A compound made up of the sterol nucleus, an 8-10-carbon side chain and an alcohol group.


A naturally occurring antioxidant found in many vegetable oils.


The term used to describe a geometric isomer of an unsaturated fatty acid where hydrogens attached to the carbons comprising the double bond are on opposite sides of the carbon chain.


The chemical combination product of glycerol and three fatty acids. Alternately known as triacylglycerol.

Unsaturated fatty acid

A fatty acid containing one or more carbon-carbon double bonds.


Hydrophobic material made of hydrocarbon, long chain fatty acids, long chain alcohols, or wax ester (ester of a long chain alcohol and fatty acid).


The process of separating the solid fraction (stearine) from the liquid fraction (olein) of an oil by cooling and filtering.

Back to Preface >

Copyright © 2016 Institute of Shortening and Edible Oils